The size, geometry and arrangement of pores can significantly affect both the activity of electrocatalysts and the performance of supercapacitors. Electrochemical impedance spectroscopy (EIS) is a powerful, non-invasive diagnostic tool for characterizing porous conductive media. To date, the impedance of porous electrodes characterized by the distribution of pore sizes has been described only on the basis of numerical models. Here, for the first time, the impedance of such systems is provided in the form of analytical solutions valid in high and low frequency range. The model enables traditional equivalent circuit fitting to impedance of electrodes characterized by log–normal distribution of pore sizes. The analytical expressions for the circuit elements give access to the electrode idealized geometry in terms of log-normal distribution. The model was applied for the analysis of the electrochemical impedance of activated carbon electrode in a sulphuric acid solution. The width of pore size distribution, mean pore radius, pore length and the number of pores can be determined from a single impedance spectrum.

中文翻译：

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通过 EIS 评估多孔电极孔径分布的等效电路


孔的尺寸、几何形状和排列可以显着影响电催化剂的活性和超级电容器的性能。电化学阻抗谱 (EIS) 是一种强大的非侵入性诊断工具，用于表征多孔导电介质。迄今为止，仅在数值模型的基础上描述了以孔径分布为特征的多孔电极的阻抗。在这里，此类系统的阻抗首次以在高频和低频范围内有效的解析解的形式提供。该模型使传统的等效电路能够拟合以孔径的对数正态分布为特征的电极阻抗。电路元件的解析表达式可以根据对数正态分布获得电极理想化几何形状。该模型用于分析活性炭电极在硫酸溶液中的电化学阻抗。孔径分布的宽度、平均孔半径、孔长度和孔数量可以从单个阻抗谱确定。